Laser-Driven Ultra-Relativistic Plasmas - Nuclear Fusion in Coulomb Shock Waves, Rouge Waves, and Background Matter

Abstract : In this grant period this PI developed new research directions and made progress in his fundamental and application research done previously for AFOSR. This PI predicted a new optical effect whereby a media with slow spatial gradient of its characteristics is found to exhibit a universal wave pattern ('gradient marker') in a vicinity of the maxima/minima of the gradient; it is common for optics, acoustics, and quantum mechanics. Among potential applications of this effect is contour-detection and tracing of large moving submerged objects in the ocean. In his recent review [2], this PI has continued his research in the extreme ultra-short pulses beyond attosecond domain, which he pioneered in his research for AFOSR long ago by proposing the way to generate so called 'zepto-second' pulses. In his paper [3], this PI predicted that an overdense plasma layer irradiated by intense light should exhibit dramatic nonlinear-optical effects due to a relativistic mass-effect of free electrons: highly-multiple hysteresises of reflection and transition,and emergence of immobile waves of large amplitude. Those are trapped quasi-solitons in the layer sustained by a weak pumping having a tiny fraction of their peak intensity once they have been excited first by higher power pumping. The phenomenon persists even in the layers with 'soft' boundaries, as well as in a semi-infinite plasma with low absorption. These effects could be used for laser fusion to deposit laser power much deeper into the fusion pallets; or for heating the ionosphere layers by a powerful radiation. This PI also continued his study of laser-excited atomic nano-structures, which were predicted by him earlier in collaboration with his post-doc Volkov in the research under AFOSR grant.